Centrifugal pulp-screen.



Wiinesses:

G. W. THOMAS. v

OENTRIPUGAL PULP SCREEN. APPfAIOATION 11.21) SEPT. a, 1909.

2 SHEETS-SHEET 1.

Invenroh Attorney- 0. W. THOMAS. GENTRIPUGAL PULP scum.

APPLICATION FILED SEPT.3,1909.

Patented N0v.'8, 1910.

2 SHEETS-SHEET 2.

wimessem I l nvenfor z I UNITED STATES PATENT car on.

CHARLES WALTER THOMAS,- or EDGEWATER, NEW JERSEY, assronon or ONE-HAL 'ro crmnnns SMITH, 0F BELLEVILLE, NEW JERSEY.

CENTRIFUGAL PULP-SCREEN.

Specification 0! Letters Patent.

Patented Nov. 8, 1910.

Application filed September 8, 1909. Sertifl No. 516,124

and State of New Jersey, ha \0 invented oer tain new and useful Tn'iprovenients-in Centrifugal Pulp-Screens, of which the following is a specification.

. The invention relates to improvements in centrifugal screens for ground-wood pulp, sulfite, and other materials, and it consists in the noreh features, arrangements, and combinations of parts l'iercina'lter-described, and particularly pointed out in the claims;

The present invention con'iprises improvements on machines of the class indicated in Letters Patent No. 809.642 granted January 19, 1.90Gto Charles lYJ'lhomas, and its object is to 'norluee'a machine of greatly increased capacity and efiici'encv and of improved mechanical construct ion.

The invention will, be fully understood from thede'tailed description hereinafter presented, reference being had to the accom- 'paiiying drawings, in which:

Figure 1 is aside elevation, partly broken away and partly in section, of a machine embodying iny invention. and Fi e, 2 is a 'horizont'al section, on the dotted line 2---2 of 1, of the same.

In the drawings; 10 designates a suitable supportin r base frame for the 'ui-it'lillivtparts of 1' 1e n'nu-hineJ I prefer toniake the body of the machine of a series of castings mounted and secured one'upon another, the lower one of said castings'ivhich is. direct] y supported .upon the l base-frame 1 0-being designated by the mi:-

meral 11, the adjacent higher casting by the'. numeral 12', the" next higher casting by the numeral I-3 and the top casting by-"the numera'l -l4. -These eastings form the station-- 'a'ry. inclosin-gshell creasing ofthe machine and in addition are constructed to perform certain duties hereinafter specified.

With-hr the casing of the machine-are inountte'd a series of vertical cylindrical screens. or baskets-15 into which the stock to" besereened delivered from a central rotar feed hopper through nozzles l7 lea inglth'erefrom and into'said screens and which screens or baskets-in the nsual ope ra tion of'thc' machine have-imparted to them a rotary motion on theirown independent I axes and at the same time a planetary or revolving motion around'the central vertical axis of the machine in a direction reversely toithat of their rotary motion. The good stock passing through the screens enters an annular chamber 18 and is conducted away, while the slivers and refuse descend through trough '19, whence they are conducted away by any suitable piping, not shown, connected with the discharge 20 from said trough.

The bottom casting 11 is of cylindrical or ring out-line, being open at its central vertical portion, and in it is formed the trough 19. The castingll at. its outer sides extends upwardly beyond the horizontal'plane' of the trough 19' and is flanged .atits upper edges, as at 21,, to receive the lower flanged edges of the outer sides of the' casting 12. The casting 11 is formed integrally with the discharge 20 from the trough 19 and with ber 18.

outer vertical portions of: the casting T1 is formed the chamber 18. 'llhelcast n g 12 15 the chamber 18 and extends upwardly to of the screens or baskets 15. At its upper 1.ip\vard ly and. inwardly, as at 25, to about the horizontal plane otithe'uppe'r ends 01 the; screens or baske'ts15. 7

ing'co'mprising center and a having gear teeth formed aroun its lower ed e to constitute-a stationary gear wheel 30;

he castin' 14 is seated on theouter portions of the p gral elbow -31 which leads to the hopper '16 ,not shown,"'for*directing the groun Won the discharge 22 from the annulancham-j about the horizontal plane of thelowerends -end the casting 12 extendsinwa'rdly o n ,a,

horizontal plane, as ut. 2.4, and 'tlienoe-,-fla r; es-

and to which will be connected the. 'i'pfin% the open bottoms of the screens and enter a,

The casting lz'is of annular shell forma tion and within its outer portions and the seated on the casting l1 and is: formed with an inner annular rertical partltio' n23 wh ch. defines the inner side 'of the'lower portion of Jlhe casting 13. is seated on the upper horizontal portion. 240i the castingi12'an'd has-atop portion 26 which is open at its=vertical center andformed around the opening-- with a flange27, u on which'isseated a casts a" isk-portion 28-ope'n at'its epending tubular ortion 29- $1128 and comprises an .l'ntea and water, brother materials to betreated, to the machine. The elbow 31 is formed '33. The shaft is and at its lower end is stepped in a hearing 39. 1

\Vithin the general casing of the machine is a casting 40 wlnchcarries the screens or port for the the driving' baskets 15 and is secured, at the sleeves 41, 5

33, which carries said casting. The central portion 42 of the casting 40 is in the form of concentric with the shaft to the vertical shaft :33- and forms the a vertical cylinder imparted to them rotary affords vertical tubularbearings 50 for the upper portions of the shafts 48. Upon the upper ends of the shafts 48 are secured the gear-wheels" 51 in mesh with idlers 52 which are carried by the plate 45) and engage the stationary gear wheel 30. During the rotation of the casting 40 carrying the baskets or screens 15, the idlers 52 against the stationary gear -wheel 30 and thereby caused to rotate and impart rotary movement to the gear wheels 51, shafts 48 and baskets or screens 15, with the result that while the, baskets or screens are revolving around the axis of'the shaft 33 they have movement on their a direction reversely to that of their planetary movement. I prefer to so time the parts of the machine that with each planetanv .movement orrevolution of the screens or baskets to, saulscrcens or baskets own axes in will have one rotation on their own axes.

rotary hopper ]0 -for the n'taterial to be:

screened. 4

' The casting/l0 below each basket; 15 is formed with a bottom cup-section 43 having at its outer portion a-discharge opening it and'a-lon its upper edges tin-annular flange or shoul er 45 to snugly encompass, without binding, the Vertical portion of the angular band 46 on the lower-edges of the basket. The sections l3 also alfordhearings 47 for .the lower ends of the vertical shafts -18 'to which the scieens or baskets are connected. The lower ends 01' the screens or baskets 1 5 areopen and the materialto be treated is fed upwardly into the baskets t'l'iron'gh their open iwer ends by nozzles 17 which connect with the: hop cast-mg 40. '1 1e nozzles,17 incline u and outwardly fromJthe-lower enof the 'hop'fierlti fora suitable distance and then turirlateral'l and upwardly and outwardly along of the sl1a-fts'48 and terminate in reasonably close relation .tothe inner, face ofthe-screens. I also preferably form the nozzles 17 "with-discharge portions of gradtally increasing the discharging} material over a reasonably The nozzles 17 inc ine upwardly, and this isa feature of advanta eslnce by reason thereof 'the materialdisch'arged -,,upwardly a must the screens-and have a-more exten ed travelover the samethan would be thecase if the has material were projected on a direct horizontal line against the screens. When the screens 15. are-arranged to rotate tb the left:

. as indicated by the. arrow 9 inFi 2, the

nozzles ,17 should exteiul-to the rig t of the. said. nozzles would .deliver the stock at pointson the'screens which had passed beyond'the field of greatest .oen-

shafts 48, otherwise trifu'gal action.

Upon the central tubular. ortion 42 of the casting -10 is secured'a p )er 1.6 and'arecarried by the'.

wardly cross-section so as to spread ate 49 which -cover-.plate- 5 4b. 1' close the upper ends of the baskets or considerable distance alongthe sha i'ts l8 and n -for example ground 'to the shaft 35 and the 3 screens 15 to prevent the unscreened or undesirable stoek or slivers froin working up over the sides of the creens and passing into the chamber 18 foitsrreened stock. In my aforesaid Letters Patent 5051,6421 tops'of the baskets are partly closed, while in the present instance the baskets are wholly closed at theirupper ends. The inverted ctually maintain said sh. ft's agailtst cen u al action tending to force them out tri are held in the bearings di' and-t-he' low'cr -ends.of the baskets-"are within the annular flanges or-shot-tlders 45 which materially aid 1n resisting centrifugal action tending to force the baskets outwardly. The arran' ement .of the castin 40 and plate 49 ehab es me tovery efi'ectua 1y secure the baskets and to lace the gear wheels 51-, 52 abovethe' bas ets instead ofbelow thein.

In the use of the wood, owe'r is applied stoe (ground wood and water) is fed through the elbow 31 to the hopper 16 and nozzles'l't', which direct plates frat enables are carried The lower ends of the shafts 48 machine for screening,

the same upwa'nlly against the inner surface" of the-screens l5, thc latter at the same time being in rotation and also carr ed-on a path around thecentral a tis of the machine.

The stock which passes through the side of the screens or baskets and is thereby relieved of slivers and the like, enters the annular chamber 18 and thence escapes or is led avay through the discharge 22. 'The stock which fails to pass through the sides of the screens descends through the open lower ends of the screens and enters the cup-sections 43, whence it escapes through the openings 414 in said sections and descends into the annular trough 19 and finally passes through the discharge 20. The rotary and planetary movements of the baskets or screens 15 are the same as the movements described for the baskets or screens in my aforesaid Letters Patent. andthereforerequire no further detailed description.

The present, invention comprises a new construction of machine employing the rotary and revolving baskets or screens whereby greater durability, convenience, efficiency and capacity are attained. A further novel feature of the present machine resides in connecting to the discharge 22 a' pipe 55 whose lower end enters a receptacle 56 which receives the screened stock and from which said stock flows away through a pipe 57, which is above the level of the lower end of the pipe 55. The screened stock forms a seal within-the receptacle 5(; for the lower end of thepipe 55', and the purpose of this seal is to deaden, as far as possible, the" air within themain chamber of the machine, so

that there may be as little interference as possible from air currents and eddies, to the passage of the stock through-the screens, and also so that the casting 40 andparts carried by it may during their movement be enabled totravel in a dead-: 1ir-ch:imber,or a chamber in which the air will simply be churnedup by said parts'during their movement. W en the casting 40 and parts carried by it more in .a dead air-chamber much less power is required to rotate them, their movement is smoother and there is wearing on the machine and the screens with less air interference are enabled to screen the stock with greater etli'ciency and capacity.

The sealing of the pipe prevents the creation of strong air currents within and through the main chamber of the machine, the air ordinarily heretofore having been driven with great force into the discharge for screened stock as an outlet.

Vhat I claim as myinvention and desire to secure by Letters Patent is:

1. In a, centrifugal screening machine, a central vertical shaft, :1 series of individual vertical cylindrical screens mounted upon and revoluble on the axis of said shaft, vertical shafts extending through the individual screens and connected therewith, gear wheels on the --u'pper"ends of said shaft above. said screens, idlers in mesh with said gear wheels, and a stationary gear in mesh tical shafts extending through the individual screens and connected. therewith, gear wheels on the upper ends of said shafts above said screens, and a stationary gear for imparting independent rotary motion to said gear wheels and screens during the revoluble motion of the screens, the said" screens each having a .cover closing its upper end, combined with a feedhop )er and discharge nozzles extending there mm to} within the screens, substantially as set fortlii 3."In a centrifugal screening machine, a central vertical shaft, a series of individual vertical cylindrical screens mounted uponand revoluble on the axis of said shaft, ver

tical shafts extending through thejindivid ual screens and connected therewith, gear wheels on the upper ends of said shafts above said screens, and a stationary gear for imparting independent rotary motion to. said gear wheels.and screens during the revoluble motion of they screens, the said screens each having a. cover closing its up-. -v

per end, combined with a feed hopperand.

discharge nozzles extendingtherefrom up-.

wardly on inclined lines through the open lower ends of the screens set forth.

substantially as 4. In acentrifugal screening machine, a central vcrtical'shaft, a frame secured thereon, a series of vertical cylindrical screens.

carried by said frame, means for rotating said shaft andframe, VBItlCBl-Sllfifi'ifi extending through said screens and-havinga bear ,ing in said -frame and connected withthe screens, means-"for rotating said screen-f] shafts and screens on their own axes, and means for feeding the stock to be' screened Ztothe interior of said screens, said framehaving portions in close relation to the lower outer edges of'said screens toresist centrifugal action-tending to force the screens outwardly; substantially as set forth;

5. Ida centrifugal screening machine, a; central vertical shaft, a frame secured thereon, a series of vertical cylindrical screens.

carried by said frame, means for rotating said shaftand frame, vertical shafts extending through said screens and having a bearing in said frame and connected withtions,. a series of vertical cylindrical screens said screens; substantially as set forth.

screen-shafts and'having, openings for the escape of stock which falls to pass through the screens; substantially as set forth.

6. Ina centrifu a1 screening machine, a central vertical sha t, a frame secured thereon affording a rotary feed hopper at its center and at its'lower portion extending outwardly to form screen-supporting secmounted .over said sections, vertical shafts extending through said screens and havinga bearin -at their lower ends in said sections, a plate 519') abovesaid screens and affording bearings for the upper ends of said screenshafts, gearing above said plate for rotating said screen shafts and screens on their own axes, means for rotating said central shaft and frame connected therewith, and nozzles leading from said hopper'to the interior of 7. In a centrifugal screening machine, a central vertical shaft, a series of individual vertical cylindrical screens mounted upon and revoluble on the axis of said shaft, vcrticalshafts extending through the individ; ual screens and connected therewith, gear wheels on the upper ends of said shafts above said screens, and a stationary gear for imparting independent rotary motion to said gear wheels and screcnsduring therevoluble motion of the screens, the said screens each having an inverted cone-shaped cover closing its upper end and each cover at' itsinverted apex havinga tubular o 'ening for the screen shaft, combined wit aplate above the screens afl'ording vertical bearings for the upper portions of saidscreen-shafts, a feed-hopper, and ,nozzles extending therefrom to within the'screens; substantially as set forth. I j V 8. In a centrifugal sereeningmachine, a vertical cylindrical screcn-entirely'closed at its upper end, means for rotating said screen. upon its own axis and revolving it about the central axis of the machine, and a rotary feed hopper'having a discharge nozzle projected upwardly through the bottom of said screen, combined with means in close relation to the lower outer edge of the screen to resist centrifugal action tending to force the screen outwardly; substantially as set forth.

9. In a centrifugal screening machine, a

central vertical shaft, a series of vertical cylindrical screens mounted upon and revoluble on the axis of saidshaft, means for rotating said screens on their own axes, means for feeding the stock to be screened to the interior of said screens, an 'inclosing casing forming a chamber for said .screens and having .a discharge for the stock whichpasses through the screens and a separate discharge for the stock which fails to pass through the screens, and means tending-to deaden the air within said chamber and prevent any strong flow of air through the same with the outgoing stock; substantially as set forth.

10. In acentrifugal screening machine, a ventral 'vertical shaft, a series of vertical cylindrical screens mounted upon and revoluhlc on the axis of said shaft, means for rotating said screens on their own axes, means for feeding the-stock to be screened to the interior of said screens, an inclosing casing forming a chamber forsaid screens and having a discharge for the stock which passes through the screens and a separate discharge for the stock which fails to pass through the screens, a pipe leading from the discharge for screened stock, and a liquid seal for said pipe-to chcck the flow of air with the stock and deaden the 'air in said- CHARLES. WALTER THOMAS.

Witnesses I ARTHUR MARION, CHAS, GILL. 

